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Le Système international d’unités évolue, la seconde et l'UTC en travaux

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La 27e Conférence générale des poids et mesures a adopté sept résolutions. Pêle-mêle on y retrouve de nouveaux préfixes (ronna, quetta, ronto et quecto), des questions existentielles sur les secondes intercalaires et des travaux préparatoires à la re(re)définition de la seconde. 

En 2018, se tenait la 26e Conférence générale des poids et mesures (CGPM) avec un vote historique. En effet, les 60 états membres de la Convention du Mètre – un traité international signé à Paris le 20 mai 1875 par 17 pays (dont la France) qui a notamment créé le Bureau international des poids et mesures (BIPM) – y votaient à l'unanimité de nouvelles définitions pour quatre unités du Système international (SI), une première.

Ainsi, le kilogramme, le kelvin, la mole et l'ampère sont désormais basés sur des constantes et la physique quantique. La seconde, la candela et le mètre avaient déjà sauté le pas des années auparavant. Nous avions retracé plus de 220 ans du SI et expliqué en détail les nouveautés dans un dossier dédié. 

La semaine dernière se tenait la 27e Conférence générale des poids et mesures (elle se tient généralement tous les quatre ans). Cette fois-ci il n'était pas question d'aussi gros changements en profondeur, mais plusieurs nouveautés sont quand même au programme.

On vous détaille les changements apportés par les 7 résolutions, qui vont bien au-delà de quatre nouveaux préfixes, avec par exemple des travaux préparatoires qui auront des conséquences tangibles sur la notion de temps et sur la définition de la seconde.

Évolution des besoins et transformation numérique mondiale

Passons rapidement sur les deux premières résolutions, qui concernent d'une part « l'évolution des besoins dans le domaine de la métrologie », et d'autre part « la transformation numérique mondiale et le SI ». Il est notamment question d'encourager le Comité international des poids et mesures (CIPM) « à élaborer une vision à long terme qui veille à ce que le système mondial de mesures demeure pertinent et qu’il réponde de manière adéquate aux nouveaux défis métrologiques ».

La CGPM encourage également le Comité « à marquer, le 20 mai 2025, le 150e anniversaire de la signature de la Convention du Mètre en présentant une nouvelle vision pour le BIPM ». Un rappel rapide sur les méandres administratifs : le BIPM est placé sous la surveillance du Comité international des poids et mesures (CIPM), lui-même placé sous l'autorité de la Conférence générale des poids et mesures (CGPM)... vous suivez ?

La deuxième résolution encourage également le CIPM à continuer « ses actions de promotion et de mobilisation afin de s’assurer que le rôle de la Convention du Mètre, en tant que fondement de la confiance vis-à-vis de la  métrologie accepté au niveau international, s’ouvre à l’ère numérique ». Il est ainsi question de « développer et promouvoir un « cadre numérique du SI », qui devra notamment adopter « les principes FAIR (Findable, Accessible, Interoperable, and Reusable [Faciles à trouver, Accessibles, Interopérables et Réutilisables, ndlr]) pour les données et métadonnées métrologiques numériques  ».

Après yota et zetta, voici ronna et quetta

La troisième résolution est certainement la plus marquante pour le grand public, avec de nouveaux préfixes pour le SI. Dans les considérants, la CGPM met en avant « les besoins de la science des données, dans un futur proche, afin d’exprimer des quantités d’informations numériques d’un ordre de grandeur supérieur à 10^24 »

Quatre nouveaux (sous-)multiples sont ainsi ajoutés :

  • 10^27 : ronna (R)
  • 10^30 : quetta (Q)

  • 10^−27 : ronto (r)
  • 10^−30 : quecto (q)

Ils s'ajoutent donc aux yotta (10^24, Y), zetta (10^21, Z), exa (10^18, E), péta (10^15, P), téra (10^12, T)... ainsi que les sous multiples équivalents avec yocto, zepto, atto, femto, pico... Le dernier changement remontait à 1991 avec l'ajout de yotta, zetta dans les puissances positives, ainsi que yocto et zepto dans les négatives.

Vous l'aurez remarqué, les puissances positives se terminent par un « a » contre un « o » dans le cas contraire. Depuis l'arrivée de méga dans les années 60, le symbole associé aux puissances positives est en majuscules (M pour méga, G pour Giga, T pour téra, etc.) alors que les puissances négatives sont en minuscules. La liste officielle des préfixes se trouve par ici

TAI, UT1 et UTC : quelle heure est-il madame sardine ?

Passons à la quatrième résolution qui nécessite de s'accrocher un peu plus à ses baskets pour comprendre de quoi il en retourne. On commence par se mettre en condition avec quelques rappels sur le TAI, l'UT1 et l'UTC (et les relations entre ces trois mesures).

Le TAI ou Temps atomique international est élaboré par le Bureau international des poids et mesures (BIPM) à partir d'horloges atomiques. Il s'agit d'une « une échelle scientifique que les astronomes utilisent pour l’interprétation dynamique des mouvements des astres naturels et artificiels. Aucun signal horaire ne le diffuse directement », rappelle l'observatoire de Paris. La précision est de l'ordre de 10 à 20 nanosecondes (suffixe en o donc puissance négative – 10^-9 –, vous suivez ?).

L'UT1 ou Temps universel « est le Temps de la rotation de la Terre déterminé par l’IERS [Service international de la rotation terrestre et des systèmes de référence, ndlr] à partir principalement de l’observation des quasars extra galactiques par la technique VLBI (Interférométrie à très longue base) », explique l'Observatoire de Paris

Il est important de noter qu'UT1 « n’est pas uniforme car la rotation de la Terre autour de son axe, ralentit sur le long terme, à cause principalement des effets d’attraction luni-solaire. De plus, notre planète est perturbée par ses constituants internes (noyau, manteau) et externes (atmosphère, océans) qui modifient sa rotation ».

UT1 « est nécessaire pour fixer la position de la Terre dans son mouvement de rotation. Il sert pour la navigation et la géodésie astronomiques, pour la navigation spatiale. En astronomie, il faut le connaître pour interpréter les éclipses, les occultations, les mesures de périodes de pulsars. En géophysique, il est, par comparaison au TAI, un témoin des irrégularités de la rotation terrestre ».

Revoir la « valeur maximale pour la différence (UT1 - UTC) »

Actuellement, et d’après les accords internationaux en vigueur, UTC ne doit pas s’écarter de plus de 0,9 seconde d'UT1. Lorsque c'est le cas, on ajoute des secondes intercalaires. Cette modification peut se faire en juin et en décembre de chaque année, mais il est déjà annoncé (via un Bulletin-C, à ouvrir avec un éditeur de texte) qu'aucun changement ne sera fait cette année. Maintenant que les préliminaires sont passés, on en arrive enfin à la quatrième résolution de la CGPM.

Cette dernière indique que la valeur maximale de différence entre UT1 et UTC (actuellement de 0,9 seconde) « fait l’objet de discussions depuis de nombreuses années, car l’introduction de secondes intercalaires qui en découle crée des discontinuités qui risquent de provoquer de graves dysfonctionnements d’infrastructures numériques essentielles, telles que les systèmes globaux de navigation par satellite (GNSS), les systèmes de télécommunication et ceux de transmission d’énergie »,

Il est aussi rappelé que les opérateurs concernés ont « développé et appliqué différentes méthodes d’introduction des secondes intercalaires qui ne suivent pas de normes convenues », ce qui peut menacer « la résilience des capacités de synchronisation qui étayent des infrastructures nationales critiques ».

La « crainte » d'une seconde intercalaire négative

Pour ne rien arranger, « les récentes observations de la vitesse de la rotation de la Terre indiquent qu’il pourrait être nécessaire d’introduire pour la première fois une seconde intercalaire négative, ce qui n’a jamais été envisagé ou testé ».

Il est ainsi décidé que « la valeur maximale pour la différence (UT1 - UTC) sera augmentée au plus tard en 2035 ». La résolution ne se mouille pas davantage et renvoie la balle au CIPM qui est en charge de proposer « une valeur maximale pour la différence (UT1 - UTC) qui permettra d’assurer la continuité de l’UTC pendant au moins un siècle » et de « préparer un plan de mise en œuvre d'ici 2035 au plus tard ».

Le sujet n'est pas nouveau. Depuis la fin des années 90, des propositions pour abandonner les secondes intercalaires reviennent régulièrement sur le devant de la scène, avec des heures intercalaires à la place (ou peut aussi imaginer des minutes intercalaires). Dans un tel scénario, la prochaine heure intercalaire serait pour l'an... 2600 environ.

Re(re)définition de la seconde en approche... enfin d'ici à 2030

La cinquième résolution s'attaque une nouvelle fois à la redéfinition de la seconde. En 1967, la seconde était définie comme étant « la durée de 9 192 631 770 périodes de la radiation correspondant à la transition entre les deux niveaux hyperfins de l'état fondamental de l'atome de césium 133 ».

C'est bien beau tout cela, mais c'est « so » années 70 et la science s'est largement améliorée depuis. Désormais, « des étalons de fréquence optiques fondés sur différentes espèces et transitions, dans de nombreux laboratoires nationaux de métrologie, ont dépassé l’exactitude pouvant être atteinte par l’actuelle mise en pratique de la définition de la seconde d’un facteur allant jusqu’à 100 ». Il est aussi rappelé que « certains laboratoires ont démontré que des échelles de temps élaborées à partir d’un ou de plusieurs étalons de fréquence optiques ont le potentiel de présenter une exactitude plus élevée que l’échelle de temps fondée sur l’actuelle définition de la seconde ».

Stop, n'en jetez plus ! La CGPM encourage donc le CIPM « à formuler des propositions lors de la 28e réunion de la CGPM (2026) afin de choisir l’espèce privilégiée, ou l’ensemble d’espèces, pour une redéfinition de la seconde et afin de définir les mesures suivantes qui devront être prises afin qu’une nouvelle définition de la seconde soit adoptée par la CGPM à sa 29e réunion (2030) ». Vous voilà prévenu, ne venez pas faire part de votre surprise dans huit ans !

Adhésion à la Convention du Mètre et dotation pour 2024 à 2027

La résolution 6 concerne l’adhésion universelle à la Convention du Mètre. Sur ce point, la CGPM s'engage « à renforcer davantage le rôle du Bureau international des poids et mesures (BIPM) et à faciliter une participation plus large à ses activités, afin de parvenir à une adhésion durable et universelle à la Convention du Mètre ». Actuellement, le BIPM revendique 64 « États Membres » – ce qui signifie « État Partie à la Convention du Mètre » dans le jargon – ainsi que « 36 États et entités économiques associés ».

Enfin, la dernière résolution définit la dotation du Bureau international des poids et mesures pour les années 2024 à 2027. Elle sera de 13,161 millions d'euros en 2024 et grimpera progressivement jusqu'à 13,762 millions d'euros en 2027.



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slubman
6 days ago
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Le genre d'articles sur NextInpact qui fait que je ne regrette pas mon abonnement.

Un article de vulgarisation sur les résolutions de la dernière réunion de la Conférence des poids et mesures.

#vulgarisation #CGPM
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It’s Official: The Leap Second Will Be Retired (a Decade from Now)

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The time has come — or will come, in 2035 — to abandon the leap second.

So voted the member states of the international treaty governing science and measurement standards, at a meeting in Versailles, France, on Friday. The near-unanimous vote on what was known as Resolution D was met with relief and jubilation from the world’s metrologists, some of whom have been pressing for a solution to the leap second problem for decades.

“Unbelievable,” Patrizia Tavella, director of the time department of the International Bureau of Weights and Measures, known as B.I.P.M. from its French name and based outside Paris, wrote in a WhatsApp message shortly after the vote. “More than 20 years of discussion and now a great agreement.” She added that she was “moved to tears.”

The United States was a firm supporter of the resolution. “It feels like a historic day,” said Elizabeth Donley, chief of the time and frequency division of the National Institute of Standards and Technology, or NIST, in Boulder, Colo. “And I wish I was there. There’s probably a lot of celebrating being done in style.”

The leap second has caused trouble since its inception 50 years ago. It was devised as a way to align the international atomic time scale, in use since 1967 and derived from the vibration of cesium atoms, with the slightly slower time that Earth keeps as it rotates. In effect, whenever atomic time is one second ahead, it stops for a second to allow Earth to catch up. Ten leap seconds were inserted into the atomic time scale when the fudge was unveiled in 1972. Twenty-seven more have been added since.

Those extra seconds were tricky to insert in 1972; today, the technical issues are gnarly. For one, it’s hard to predict exactly when the next leap second will be needed, so computing networks cannot prepare for orderly, regular insertions. Different networks have developed their own, uncoordinated methods of incorporating the extra second.

Moreover, modern global computing systems have become more tightly intertwined and more reliant on hyper-precise timing, sometimes to the billionth of a second. Adding the extra second heightens the risk that those systems, which are responsible for telecommunication networks, energy transmission, financial transactions and other vital enterprises, will crash or fail to synchronize.

As a result, unofficial time systems have slowly begun to displace the world’s official international time, Coordinated Universal Time, or U.T.C. Eliminating the leap second is seen as a way of preserving adherence to U.T.C. by making it a continuous time scale rather than one that is episodically interrupted.

“The most important issue is the preservation of the concept that time is an international quantity,” said Judah Levine, a physicist at NIST. He called the Versailles decision “an incredible step forward.”

Russia voted against the resolution; Belarus abstained. Russia has long sought to delay abandonment of the leap second because its GLONASS global navigational satellite system incorporates the extra seconds, unlike other systems such as GPS, which is operated by the United States. With Russia’s concerns in mind, the leap second is not scheduled to be dropped until 2035, although it could happen sooner.

Resolution D calls for U.T.C. to go uninterrupted by leap seconds from 2035 until at least 2135 and for metrologists to eventually figure out how to reconcile the atomic and astronomical time scales with fewer headaches. The international time standard would be severed from time as told by the heavens for generations to come.

But rejoining those two time scales was imperative, said Rev. Pavel Gabor, an astrophysicist and the vice director of the Vatican Observatory Research Group in Tucson, Ariz. He said that atomic timekeeping was just one example of how the world was becoming incomprehensible to the average person, and that scientists had a responsibility to help people feel in control of their lives.

“I think sensitivity to this mistrust of elites, mistrust of experts, mistrust of science and institutions, that’s something that’s a very real problem in today’s world,” he said. “And let’s not contribute to it.”

Steps remain in the elimination of the leap second. Although the B.I.P.M. is responsible for universal time, the International Telecommunication Union, or I.T.U., is responsible for transmitting it. The I.T.U.’s World Radiocommunication Conference in Dubai, United Arab Emirates, will also vote on the issue next year. Felicitas Arias, the former director of the time department at the B.I.P.M. and now a visiting astronomer at the Paris Observatory, said that negotiations between the two organizations convinced her that the I.T.U. will support the Versailles vote.

“Now we see really closer the moment to have continuous time,” she said, applauding the vote on Friday. “And this is something we have been dreaming about for a long, long time.”

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slubman
10 days ago
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So the #leapsecond is going bye bye soon
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LEGO Icons 10307 – Eiffel Tower: Say Bonjour to the tallest and second largest LEGO set ever [Review]

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LEGO recently revealed their latest entry into their Icons theme – the LEGO Icons 10307 Eiffel Tower. This massive set has 10,001 pieces (making it the second highest part count behind the 31203 World Map mosaic), and at 149 cm / 58″, stands as the tallest LEGO set ever. It will be available from the LEGO Shop Online starting November 25th for US $629.99 | CAN $799.99 | UK £554.99. We’ve been fortunate enough to get to look at an early copy, so come along as we build this key piece of the Paris skyline!

The LEGO Group provided The Brothers Brick with an early copy of this set for review. Providing TBB with products for review guarantees neither coverage nor positive reviews.


Other LEGO Eiffel Towers

This isn’t the first time LEGO has released a set featuring this iconic landmark. In fact, it’s been a recurring theme for almost two decades.  Things started off in 2005 with  LLCA25 Las Vegas Skyline, Eiffel Tower, a LLCA Ambassador Pass Exclusive set. In 2007 the general populace saw the release of the 3428 piece 10181 Eiffel Tower 1:300 Scale. In 2013 we had the 21019 The Eiffel Tower Architecture set, followed by another Architecture entry, 20144 Paris in 2019. 2020 had a bit of fridge decoration with 854011 Eiffel Tower Magnet Build. And, most recently, in 2022 we had the 40568 Paris Postcard

While each of these sets has things to recommend them, they were all limited by the elements available at the time, and by the constraints of recreating such a huge structure in a very small scale. Even the 10181 Eiffel at 1:300 suffers from a very blocky look. But this time LEGO has gone all out, creating something closer to 1:216 scale. 

For the curious, since the real tower is 1083′ tall at the tip, a minifigure scaled version would have to be about 1:44, or over 24′ tall. Reducing all the way down to the nanofigure (the tiny minifigure trophy/statue) scale of about 1:165 results in a tower about 6.5′ tall. Some might argue that LEGO could have gone for that benchmark with this set, but c’mon. This one feels big and expensive enough already, thank you.

Finally, a word on color. Did you notice anything about all the sets above? They all use either light or dark grey to portray the tower. And that’s not correct! In fact, it’s never been grey! Since 1968 the tower has been painted in what’s called “Eiffel Tower Brown”.  I get why LEGO has needed to opt for grey elements, but it does downgrade the accuracy of every model a fair bit.


Unboxing the boxes

The outer packaging for this set helps set the tone for the building experience. It’s massive – a 15″ by x18″ by 22.5″ box, tab sealed along two sides. The overall look is the standard “adult collector” packaging, with a black background, minimal logos, a greeble strip along the bottom, and a mandated 18+ age range. I normally gripe about that mandate, and once again the set could probably be handled by a younger builder, but only one with a severe overabundance of patience. This is not a set aimed at the casual builder.

The front of the box shows the full tower, and has a small inset graphic on the upper right touting the dimensions of the set ( 58.5″ / 149 cm high and 22.5″ / 57 cm wide).

The short sides of the box show the tower at close to 1:1 scale, with the image wrapping around onto the top of the box.

The back of the box has another large shot of the LEGO tower, along with insets showing the four-part construction and a view looking up from the base. There’s also a shot of the real-world tower, and a lifestyle photo of the set taking up someone’s entire kitchen table.

Opening up the flaps reveals a portrait and quote from Gustave Eiffel, translated into several languages. (Different languages on either side, too!)

“There is an attraction and a charm inherent in the colossal that is not subject to ordinary theories of art… The tower will be the tallest edifice ever raised by man. Will it, therefore, be imposing in its own way?”

Good question, Gustave.

Moving on, like other giant sets like the 75192 UCS Millennium Falcon, there’s more unboxing to do. Inside the outer box are three smaller boxes. As indicated by the graphics on the leading edge, each box contains the parts needed to build a section of the tower.

In addition to the friendly numbering in the upper left corner, the section of the tower contained in each box is also indicated by the graphic on the front of the package. The portions of the tower that aren’t included in a section are shown as tan render, making it easy to tell what you’ll be working on.

Since each box is so self-contained, we’ll be looking at each individually.


Box 1 – The Base

The first box, unsurprisingly, focuses on the the bottom of the tower. Looking closely at the art on the box, you can see that this step won’t include any of the actual metal tower at all; just the ground and greenery at the base.

Inside the box are fourteen numbered part bags, five unnumbered bags containing large plates, and four loose 16×16 black plates.

There is also a paper envelope that contains the instruction manual.

The instruction booklet, helpfully labeled “Book 1”, is center stapled and 92 pages long.

Like other Icon and “adult collector” type sets, the first few pages give some background on the subject at hand. The set’s design team also get some coverage, with a two page spread. Lead designer Rok Žgalin Kobe talks a bit about the design challenges and how the team approached them.

While this set doesn’t offer any new molds, it does have a wide range of interesting parts and recolors. For this first box, the standouts were these road baseplates in olive green, and dark tan.

The base for the tower starts off by constructing the four corners. This is an early hint at how many times you’ll be seeing “x4” or “x8” or “x10000” while working your way through the build. A small Easter egg comes in the selection of colors for the interior bricks – the red, white, and blue mirror the hues of the French flag that will eventually top the tower.

Next up are four sets of braces that will form the inner edges of the base.

Connecting everything, you at last start to get a feel for how massive this set is going to be. The base fits on my work table, but only just. A layer of road baseplates helps lock things together.

The first X16 step is making these small flower beds.

They slot into the olive green bases, and create the classic quad that was originally under the Eiffel tower.

The next step is adding the small buildings under the base of each leg. The interior bricks are color coded – red for North/South and yellow for East/West.

Adding details to the base means that the meager “x4” construction multiplier is about to be tossed in favor of finger-shredding levels of repetitive detail building. First up are 32 stacks of 1×1 round plant plates. Then a slightly more complex 3-piece lamppost at x48. You think you’re getting a break with only x8 on the small trees, but putting the leaves on the center stalks is a warning.

The warning was this: “You’re about to enter a world of pain.” There may be only 8 of these larger tree assemblies, but each one consists of 30 1×1 round leaf elements, 5 central branches, and a 3-piece trunk. That’s a total of 38 pieces per tree, or 304 parts for the group. Which is more pieces than you see in some entire LEGO sets. And did I mention the branch/leaf combos are really hard on the fingers to assemble? Well, they are.

They sure do look nice, though.

Placing all of the decorative elements on the base completes box one. Be forewarned that you’re going to be putting the trees and lamps back onto the base throughout the rest of the build. They’re super easy to knock off.

But, putting the camera down at “ground level” you really get a feel for how immersive this model is going to be when complete. It already looks like a gorgeous day in the park.


Box 2 – The Base of the Tower

Box two contains the base level of the tower. Looking at the box art, you can see the small slice of the overall construction covered. But when you open it up, you realize there’s a LOT of building in this portion.

Inside the box are 22 numbered part bags, covering steps 19-40. There are also two unnumbered bags containing roller coaster track and flex tubing, and a last unnumbered bag with grill plates.  A second carboard envelope identical to the one in box one rounds out the cast.

Inside the envelope is the second instruction manual. This one is 200 pages long and perfect bound. It doesn’t have any additional informational splash pages, but is focused only on the building steps.

Parts that caught my eye in this box were these Roller Coaster ramp pieces. This the their first appearance in dark grey, and you’ll get 8 of them.

Construction starts with a x2 assembly of the tower’s leg. As we saw in the base, the north/south and east/west legs are color coded red and yellow. This means that rather than a x4 slog, you have to go through two sets of x2, with the only difference being the accent color on a few plates and tiles.

Each side of the leg has similar construction – a beam of stacked plates topped with cross-beams.

These beams attach with clips to a square plate base, with Technic beams that will be used to join the four sections together. Note the yellow 2×2 triangle tile – that’s one of the colored elements I was mentioning.

A bit of design that caught my attention is the mount for the color-coded double-decker elevators. A 2×2 turntable is braced at an angle by use of two 1×1 quarter circle tiles that wedge in-between the studs on the surrounding brick. This allow for a two-stud connection point, a nice bit of stability as these leg assemblies are going to get knocked around a lot while trying to get everything attached.

The tan plate is the base of the leg, with the Technic beams at the top forming a “studs down” ring at the top.

After an hour or two of building, all four legs are assembled and ready to attach to the base.

The legs slot into the base and lean together, matching up using the red and yellow color keys. The Technic beams at the top are connected, and a layer of plate is applied to help get things into alignment. I had some issues at this point, as the plates at the top of each leg kept detaching due to stress from not having them “lean in” at the correct angle on all four legs. As it was, you can still see some real bowing of the plates on the connection ring at the top.

After some work on aligning things and adjusting the crossbar assemblies, though, the top of the first section was more or less level. Sort of.

Things were still very wobbly, so I was glad to see the next building section was adding some support structures. Each of the four sides gets a decorative arch. These are mounted studs-down, attaching in the gap between the tops of the legs. The lower portion is mounted on 1×2 hinge bricks, allowing the main body to swing out to align with the legs.

As hoped, the arches added a bit of locking to the upper edge of the legs. It’s still very fiddly, though, and the square brace is prone to pop off. And when you try and seat it firmly, the detail elements on the interior of the legs want to fall off. So it’s not perfect, but once you have it more or less set, you can leave it. The weight of the upper levels will eventually help ensure everything is forced into alignment.

Pausing to look at the structure, it really is a beautiful build. You may note that a lot of the cross beams don’t read as level right now – but going back through and tapping them all into visual alignment really needs to be saved for later. The addition of some flex tubing along the bottom edge helps clean up the lines and reinforce the look of the arches.

I had thought box two was going to be “just” the lower legs, but there’s more building to be done. The lower part of the 2nd tier awaits! Of course it starts out with putting 144 1×1 round plates along the outer edge. What fun!

The center ring of the level has a bit of clever construction. The grates are all mounted on 1×2 hinges, and are locked into the correct angle by leaning against the modified 1×1 bricks with side studs.

Returning to the outer ring, an outer layer of 1×2 ingot tiles adds some nice texture.

Turns out there’s a bit of meaning to those ingots, too. One of the factoids spread throughout the instructions gives us the inside scoop:

“Gustave Eiffel engraved the names of 72 French scientists, engineers and mathematicians into the tower. On the LEGO model the names are represented by 72 Ingot pieces.”

The outer and inner rings are connected with some beams, and a layer of grates are placed on top to lock things together.

Then we return to the outer edge, adding some complex (and repetitive ) scroll work.

The next step has 128 1×1 round plates as part of the edging. We’re rapidly closing in on LEGO Art mosaic levels of stud placement.

I can’t really complain about the end results, though. The detailing looks incredible.

Finishing the instructions in Book Two, we can slot the start of the 2nd level into place. this also has the benefit of squaring up the lower legs and providing a safe “push point” to try and lock together the lower leg construction. Just don’t go crazy and push too hard. You really don’t want to have to start over.


Box 3 – The Top

Entering the final stretch, we move on to box three. As the illustration shows, this one contains most of the vertical height of the tower.

Inside the box was the expected white carboard envelope that contains the instruction book. A surprise was a second white box that contained some of the part bags. These bags were spread out across the building areas (Step numbers from the 50’s, 60’s and 70’s) with no obvious reason for them to be grouped together.

In total, there are 34 numbered parts bags, spanning steps 41 through 74. There’s also a final unnumbered bag containing grill plates.

The final instruction book is perfect bound and 252 pages long.

The interesting pieces for this box are more rare-ish and recolored parts.  The 2-plate tall blocks in dark grey are nice to get in quantity, and the dark grey hotdogs are the height of French cuisine.

Things start out with building the legs for the 2nd level. The basic construction is very similar to the lower legs, starting out with a square plate base with Technic beam bracing.

The legs themselves area also nearly identical in styling, connecting to both top and bottom plates via clips.

There isn’t any red/yellow color coding on this level, so orientation isn’t super important. You do build two of the legs first, attach them, then go back for a nearly identical build for the other two. The shorter spans and closer Technic connections means that this level is a lot more sturdy feeling that the lower level.

Locking everything together, have a nice solid section of tower. The inverted Technic beams at the top do have the same problem of wanting to pop off the plates at the top of the legs due to the flex from non-perfectly aligned leg angles.

Speaking of the lower level, here’s a shot of the two together. You can get a feel for how things are starting to come together. We’re also to the point where my (rather large) backdrop is struggling to keep up with the size of the set.

The third base follows the same strategy seen at the join between the first and second levels. A series of plates and Technic beams form a hollow for the previous section’s top to slot into.  The form factor is decreasing, making this a slightly faster build.

At the center of the level, a hole for a Technic beam is exposed, another concession to the need for stability as things go vertical.

Another cute detail is the use of those dark grey hot dogs for curved metalwork.

The center strut is made from four brick-built beams attached via clips at the top and bottom.

Support beams are connected with Technic rods and locked into the center of the assembly. Small colored elevators are added, giving the model a bit of a “Seek and find” treat. A second set of large beams go around the central tower, creating the framework for the vertical rise.

More latticework is built, again with a very similar build to what we’ve seen on the earlier levels. These slot into the larger framework and require quite a bit of fiddling to get all the crossbeams aligned.

This looks like a complete section, but it’s actually just the first half of the third level. There’s still more building to go!

You can slot it onto the second tier to test the fit, if you want.

 

The next bit of tower starts with another support beam tower, with another couple of elevator cars. Another set of brick-built beams will surround this core.

The crossbars are getting a lot smaller as we reach the top. The same general set of parts is still used, though. This does unify the look, as a change in technique would have really stood out.

Once this section is complete, it attaches to the lower half and is secured with four 2×2 tiles at the join.

At long last we’ve reached the top of the tower. A small ring of windows is fleshed out with transparent 1×1 and 1×2 plate.

The cap continues with more grey hot dogs. The pigeons love ’em.

And voila! The very last thing to be put together is the french flag. A welcome burst of color after slogging through a mostly monochromatic build.

Setting the cap on top of the third level completes the set!


The finished model

The completed tower stands just under five feet tall. It’s pretty glorious. At least…it was.

You see, after spending 20+ hours this week on assembling and documenting this build, I was a little punch drunk. When it came time to move my backdrop and put the Eiffel Tower on the floor so I could actually have enough clearance for the whole thing, I didn’t notice that my lighting kit was in a precarious state. The cords were stretched too tight and…well….

So the final batch of photos for this will be a bit delayed. For right now, I’ve used placeholders from the LEGO press release. We’ll get things updated as soon as we can!

The metalwork looks great, although you’ll want to spend some time aligning the crossbars once the weight has settled.

Even the view from the underside is accurate to the Eiffel tower. Not that anyone is likely to casually experience this angle in person.

The red and yellow double-decker elevators are a fun detail to look for, and a tiny spot of color in all that (inaccurate) dark grey.

The view from the ground is really nice. This is the landscape as it existed when the tower first opened. These days, according to my friend Mara, it’s more just long lines of tourists waiting for a chance to ride up to the top.

There are even little notches in the base so you can get your fingers in there to brace things when trying to pick things up. Just be sure to break it into the separate tower sections first!

There aren’t any play features, but that’s probably for the best. Although the completed model is pretty sturdy, you don’t want to push you luck with moving it around a lot, or staging adventures like the start of the first Christopher Reeve Superman movie. (Although a nanoscale Superman and Lois would almost be in scale…)


Conclusion and recommendation

If feels like LEGO has been leaning into “super massive” sets in recent years. Capitalizing on larger budgets of adult fans, they’ve pulled out the stops and gone for spectacular builds that show just what LEGO bricks can make when you have enough of them. It’d be hard to describe The Eiffel Tower set in any other terms. It’s spectacular. And expensive.

The build gets a bit tedious and finger-bruising at times from repetition, but the designers did a good job of varying the order of build tasks so it manages to avoid feeling like too much of a slog. There are interesting build techniques to learn, and this model is a master class in detail work. I can’t recommend it as a speed build challenge, as you’ll get the most enjoyment if you can take your time and appreciate each part of the construction.

For $630 US, you get 10,001 pieces, or 10,000 pieces and a brick separator if you want to count it that way. That works out to just over six cents per piece – not a bad number. It’s unlikely that too many people will be using this as a parts pack (unless they need a LOT of dark grey), but there are a good mix of elements. The downside is that many of them are massive quantities of smaller parts, and there are no new molds (and only a couple of recolors) to tempt the part-hounds. Maybe that would be different if LEGO had licensed the actual Eiffel tower brown color and done a special run of parts just for this set. (Think Maersk Blue on steroids.) But I shudder to think how expensive a set that like would have been.

The sheer number of times LEGO has revisited the Eiffel Tower in recent years says there’s likely to be some real consumer interest in this set, but there’s still the issue of what to do with it once you’ve built it. It’s far too large to be easily displayed. But I suppose if you’re shelling out the money for this kit, you probably already have somewhere in mind.

How about you? Do you have room in your heart (and your wallet) (and your home) for this set? Let us know your thoughts in the comments!


Icons 10307 Eiffel Tower will be available November 25th from the LEGO Shop Online for US $629.99 | CAN $799.99 | UK £554.99. It may also available via third-party sellers on Amazon and eBay.

The LEGO Group sent The Brothers Brick an early copy of this set for review. Providing TBB with products for review guarantees neither coverage nor positive reviews.


Check out our full gallery of images

The post LEGO Icons 10307 – Eiffel Tower: Say Bonjour to the tallest and second largest LEGO set ever [Review] appeared first on The Brothers Brick.

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slubman
11 days ago
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Interesting #LEGO set to look at, but way too expensive to buy.
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La CNIL inflige à Discord une amende de 800 000 euros

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Le service de messagerie est sanctionné au titre de plusieurs manquements aux obligations imposées par le RGPD. La Commission nationale de l’informatique et des libertés rappelle néanmoins les efforts consentis par la société pour se mettre en règle.
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slubman
12 days ago
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Artemis I releases 10 cubesats, including a Moon lander, for technology and research

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The Artemis I mission, the first flight of the Orion spacecraft and SLS, is now underway after a successful launch from Pad 39B at the Kennedy Space Center at 1:47:44 AM EST (06:47:44 UTC) on Nov. 16.

Artemis I not only launched the Orion spacecraft to the Moon but also 10 6U CubeSats, most massing around 14 kilograms, which were ejected from the ICPS upper stage after the trans-lunar injection burn following launch.

These CubeSats will fly to various destinations including the Moon, asteroids, and interplanetary space. They will study various facets of the Moon and interplanetary travel, ranging from navigation techniques to radiation and biology. One of them is even planned to conduct a soft landing on the lunar surface.

Thirteen CubeSat missions were initially chosen during the 2015-2017 timeframe to fly aboard Artemis I (then known as Exploration Mission-1 or EM-1), but three of them were not ready by the final deadline to process the payloads for launch.

The Lunar Flashlight, the two Cislunar Explorer nanosatellites, and the CU-E3 were unable to be delivered due to various technical and pandemic-related issues. They may be processed for later launch opportunities.

Installation of the NEA Scout and Lunar IceCube satellites in the ICPS upper stage of SLS on July 14, 2022. (Credit: NASA)

Ten CubeSat missions were delivered to the Kennedy Space Center and processed for flight during the summer of 2021. They were mounted on a payload ring on the ICPS second stage along with an avionics unit that controlled the deployment sequence.

Two of these missions are NASA’s and directly developed and operated by NASA centers. Other missions are developed by universities, small and large aerospace companies, and research institutes in cooperation with NASA.

The European Space Agency (ESA), the Italian Space Agency (ASI), and the Japan Aerospace Exploration Agency (JAXA) are involved with CubeSat missions on this flight as well.

CubeSats on Artemis I

The Lunar IceCube mission is a collaborative effort between Morehead State University, the Busek Company, and the NASA Goddard Space Flight Center. Lunar IceCube will go into a high-inclination elliptical orbit with a 100-kilometer high perilune (the lowest point of the orbit around the Moon) and map volatiles on the lunar surface.

Lunar IceCube is equipped with one instrument, the Broadband InfraRed Compact High-Resolution Explorer Spectrometer (BIRCHES). BIRCHES will use its spectrometer capability to determine major minerals on the lunar surface.

The Solid Rocket Boosters tumble through the air after separation as the Core Stage RS-25s continue pushing SLS into orbit. (Credit: Stephen Marr for NSF)

The NEA (Near Earth Asteroid) Scout was developed by the NASA Marshall Space Flight Center. It will conduct a flyby of a small asteroid and collect data on its environment, with the help of a solar sail measuring 86 square meters and several lunar flybys to get the spacecraft on the proper path to the asteroid.

Asteroid 2020 GE is the planned target for the NEA Scout, though depending on the exact launch time and date, this could change. 2020 GE is 18 meters in diameter, and this would be the smallest Solar System object ever explored by a spacecraft to date.

NEA Scout’s objective is to fly by and characterize an asteroid between one to 100 meters in diameter. The spacecraft is carrying a science-grade camera with electronics based on the context camera for the Orbiting Carbon Observatory-3 (OCO-3) platform installed on the ISS.

Asteroids like 2020 GE are part of a family of objects that are not well understood, but objects of this size are capable of causing major damage to cities if they hit Earth on the right trajectory. The near-earth population of asteroids may also be mined for resources in the future, for use on Earth or by bases on the Moon or in Earth orbit.

Artist’s impression of the BioSentinel CubeSat in deep space. Credit: NASA

The BioSentinel mission was developed by the NASA Ames Research Center and is the first NASA mission to send living things to cislunar space since December 1972, with three identical biological payloads available as comparison references. This includes one in low Earth orbit aboard ISS. The budding yeast Saccharomyces cerevisiae is being carried aboard the CubeSat. 

The yeast will be activated after inflight checkouts and the lunar flyby. It has been selected because of its similarity to human cells and how they repair double-strand breaks in DNA caused by ionizing radiation. The metabolic activity and culture growth of the yeast cells will be evaluated as an indicator of successful damage repair to the cells’ DNA.

The BioSentinel CubeSat also carries sensors to measure radiation in the cislunar environment. The CubeSat will be outside of the Earth’s protective magnetosphere. Therefore, it will be exposed to solar wind and cosmic rays that could cause damage to astronauts’ DNA when they venture out that far on future Artemis missions. 

The NASA-funded, Lockheed Martin-built LunIR CubeSat is a technology demonstrator that will conduct spectroscopy and thermography on the lunar surface.

Reflections on achievement. SLS lifts off on its first flight. (Credit: Julia Bergeron for NSF)

While one image of the Moon from under 20,000 kilometers will be categorized as mission success, the LunIR is planned to take several dozen images of the Moon and map it using an infrared instrument utilizing a closed-cycle mini cryocooler to keep the detector at its optimal temperature.

The cryocooler will be used on the Psyche and Europa Clipper missions and LunIR is set to be its first space test. The cryocooler and infrared sensor will be stress tested once the primary mission is over, by imaging the Moon, the Earth, then the Sun.

Afterward, it will go back to imaging the Moon and Earth, and the detector will be checked for any damage caused by the Sun.

LunIR will conduct a flyby of the Moon but will not enter orbit. It will utilize reaction wheels to point itself in the correct direction at any given time during the flight, but it does not have any other propulsion system. It will end up in a heliocentric orbit.

CuSP CubeSat shown assembled. (Credit: NASA)

The CubeSat for Solar Particles (CuSP) will likewise orbit the Sun, and it will use three instruments to measure radiation and magnetic fields from our local star. The satellite, developed by the Southwest Research Institute, the NASA Goddard Space Flight Center, and NASA JPL, will use a cold gas thruster system for propulsion.

The launch-Map satellite is sponsored by NASA’s Science Mission Directorate (SMD). This CubeSat was developed by Arizona State University in Tempe, and its mission is to image the southern polar region of the Moon’s surface. The satellite will map hydrogen-rich compounds like water around Shackleton Crater.

The Italian-built ArgoMoon CubeSat was built to take images of the ICPS upper stage during the CubeSat deployment because the ICPS wasn’t capable of sending telemetry after the trans-lunar injection burn. The Italian company Argotec designed this satellite and built it for the Italian Space Agency.

ArgoMoon is equipped with two cameras and an optical communications system, along with autonomous navigation and nanotechnology demonstrations. The CubeSat will fly by the Moon and enter a heliocentric orbit.

The Team Miles CubeSat will demonstrate hybrid plasma and laser thrusters invented by Wesley Faler, the head of the nonprofit group Fluid and Reason, LLC. The team won the CubeQuest Challenge and their concept was selected for flight.

The Team Miles CubeSat being prepared for launch. (Credit: NASA)

Team Miles will also test an S-band software-defined radio as well as deep space navigation. The technology and intellectual property developed will be used by the commercial company Miles Space.

The EQUULEUS spacecraft was developed by the University of Tokyo and JAXA. It is meant to measure the plasmasphere around Earth as well as to demonstrate water steam propellant.

As part of this demonstration, EQUULEUS will make several lunar flybys and travel to the L2 point in the Earth-Moon system. This is the same Lagrange point used by spacecraft like JWST.

Another Japanese spacecraft rounds out the Artemis I CubeSat complement. OMOTENASHI, Japanese for “welcome,” is a lunar landing demonstration commissioned by JAXA. If it succeeds, Japan would be the fourth nation to successfully land a spacecraft on the Moon, after the United States, Soviet Union, and China.

After the CubeSat enters lunar orbit with cold gas thrusters, it will deploy a surface probe to land somewhere on the lunar surface. This probe will be deorbited with a solid rocket motor and is designed to use an airbag and a metal shock absorber to achieve a semi-hard, survivable landing at less than 50 meters per second.

OMOTENASHI’s orbiting module is equipped with a dosimeter developed after the Fukushima nuclear power plant disaster in 2011, while both the lander and orbiter are equipped with a 430 MHz UHF radio that can be detected by enthusiasts.

Image from Orion after deployment from the ICPS. (Credit: NASA)

Charging, Launch, and Deployment

Artemis I finally launched on Nov. 16, 2022, after months of delays and two scrubbed attempts in the August-September timeframe. After the installation of the CubeSats in the ICPS upper stage, concerns arose about the effect delays could have on the satellite missions.

The satellites’ onboard batteries were charged before payload installation on the upper stage, but some of them could not be recharged due to a lack of access. After the SLS was rolled back to the VAB in September, some satellites – those that could be accessed – were recharged.

The BioSentinel satellite’s yeast payload was cooled before installation to preserve the viability of the experiment. The effect of the mission’s cumulative delays on BioSentinel’s experiments remains to be seen, as does the effect on the other CubeSats.

After Artemis I’s successful launch and trans-lunar injection burn, the 10 CubeSats were deployed starting four hours after launch and finished the process after eight hours. 

Six CubeSats have been heard from as of publication: EQUULEUS, LunIR, CuSP, LunaH-Map, ArgoMoon, and BioSentinel. It is hoped that if a CubeSat had lost its electrical charge during the mission delays, the spacecraft’s solar arrays would eventually catch sunlight and recharge the craft’s batteries themselves.

Regardless of the success or failure of individual CubeSats, the emergence of this class of spacecraft has enabled the testing of new technologies with less cost and at a faster pace than in the past, though also with a greater risk of failure. As Lockheed Martin LunIR program manager John Ricks stated “we’re taking high risk in the hope of getting this high reward payoff.”

(Lead image: Launch of Artemis I at 1:47 am EST from Kennedy Space Center. Credit: Nathan Barker for NSF)

The post Artemis I releases 10 cubesats, including a Moon lander, for technology and research appeared first on NASASpaceFlight.com.

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slubman
13 days ago
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The #Orion capsule is the main star of the show, but this article provide information on the 10 #cubesat that were also launched on #Artemis 1
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Evernote’s Next Move: Joining the Bending Spoons Suite of Apps

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Today we are pleased to announce that Evernote has agreed to join Bending Spoons, a leading developer of stand-out mobile apps.

In the deal signed between Bending Spoons and Evernote, Bending Spoons agrees to take ownership of Evernote in a transaction expected to complete early in 2023.

For Evernote, this decision is the next strategic step forward on our journey to be an extension of your brain. The path we’ve taken in recent years—rebuilding our apps in order to expand Evernote’s utility and deepen its appeal—has made possible new features, deep focus on our customers, and ultimately, an #everbetter productivity solution on the cusp of the next stage of innovation and growth. Teaming up with Bending Spoons will speed that journey, accelerating the delivery of improvements across our Teams, Professional, Personal, and Free offerings.

As I write this blog post, our new collaborative editing capability, which allows multiple people to edit the same note simultaneously, and individuals to edit the same note on multiple devices without note conflicts, is in early days of beta testing around the world. At the same time, we are within weeks of beta-ing our new support for Office 365 calendars—another much anticipated step forward for our customers. Of course, our drive to improve Evernote includes smaller changes, too. Whether you’ve wanted mini-sidebars on tablets, new preference menu options, iOS and Android widgets, drag & drop for tags, or even the ability to choose where to start a new note (Hint: it’s either in the title or the body; you now get to set the default), customer-centric innovation continues with every release.

While ownership is changing hands, our commitment to keeping your data safe and secure remains as steadfast as ever, and the Evernote you know and love will continue to thrive. Joining Bending Spoons allows us to take advantage of their proven app expertise and wide range of proprietary technologies. Even a small glimpse into their vibrant suite of apps, including Splice for video editing and Remini for AI-assisted photo editing, demonstrates why about 100 million people rely on Bending Spoons products every month. Bending Spoons has built a remarkable business with strong financials and has the ability and resources to propel Evernote forward.

Together, we share a vision for Evernote as a powerful, intuitive extension of your brain. Everything we do at Evernote is focused on helping our customers remember everything and accomplish anything. We look forward to the continued pursuit of that mission with you, our customers and partners, now as part of Bending Spoons.

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slubman
13 days ago
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I suppose it’s time to finalize the migration to #JoplinApp
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